Apple and Google are among a number of technology companies being investigated by US lawmakers over the use of tracking technology in mobile devices.
The US House Energy and Commerce Committee is concerned that smartphone developers have deployed tracking technology that may breach privacy regulations.
The Committee sent letters to Apple, Google, Microsoft, Nokia and RIM to ask what location data their mobile devices track, use, store and share.
The letters asked the companies whether the data is automatically transferred to their businesses, or to other devices or third parties.
The lawmakers also questioned the firms on whether smartphone users are given opportunities to prevent the tracking of their data, and if so, how.
The investigation comes on the heels of recent media reports claiming that certain operating systems are tracking and storing information on users’ locations.
Researchers Pete Warden and Alasdair Allan reported that iPhone and 3G iPads running iOS 4 keep an archive of user data which can be transferred to PCs and migrated over devices.
Apple chief executive Steve Jobs denied the reports and accused Google of tracking users with the Android platform.
Google declined to comment on the accusations, but said more broadly that all location sharing on Android is opt-in.
“We provide users with notice and control over the collection, sharing and use of location in order to provide a better mobile experience on Android devices. Any location data that is sent back to Google location servers is anonymised and is not tied or traceable to a specific user," the firm said in a statement.
US senator Al Franken is seeking to call executives from Apple and Google in front of a government committee on 10 May to testify.
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